Nano-Brass:  Bimetallic Copper/Zinc Colloids by a Nonaqueous Organometallic Route Using [Cu(OCH(Me)CH₂NMe₂)₂] and Et₂Zn as Precursors

Abstract

We present a synthetic approach toward alloyed Cu/Zn nanoparticles using [Cu(OCH(Me)CH 2 NMe 2 ) 2 ] and Et 2 Zn as precursors. The thermolysis in the hot coordinating solvent hexadecylamine, HDA, leads to the formation of nanoscale, colloidal Cu/Zn systems with zinc contents (by EDX) of 5, 30, and 65%, respectively. All systems have been analyzed using UV/Vis spectroscopy, transmission electron microscopy, EDX, and selected area electron diffraction (SAED). These analytical data suggest that alloying between zinc and copper takes place, revealing crystalline phases of CuZn and CuZn 2 besides Cu as components of the particles in the case of higher zinc concentrations. The characteristic surface plasmon resonance (UV) for pure HDA-capped copper colloids at 558 nm, still observed for copper-rich alloy particles, disappears for zinc-rich particles.